Updated: Feb 27, 2020
I believe Bomba and I cracked the code on this reverb! Until yesterday, I was using the reverb layout as published by previous efforts to document #002. The reverb worked but was very low levels and needed to be driven hard to sit well alongside the dry mix. The reverb tone was very dark as well which made it less useful other than a really low-level wash. I enhanced the contrast on gut shots of #001 and #002 and looked again at the hand-drawn schematic to see if there was anything to learn.
Sure enough, reworking the 2k2 resistor to tap into the reverb transformer green (RCA send) and connecting to the 100R/Cathode resistor & cap pair, is correct, rather than the 2k2 in line with the signal coming back from the RCA return. The RCA return is connected to the grid and 100k resistor. Now, the reverb sits extremely well in the mix compared to the dry signal. It's much brighter too! Not crazy bright, but "just right" to my ears AND I don't have to drive my reverb controls almost all the way even with a 5751 driver tube.
Attaching the latest layout and supporting pictures. As always, the latest layout can be found here: https://github.com/colganr/steel-string-singer-sn-002/tree/master/Circuit